Future prospect for activity-based models
# Integrated across days of the week
The current operational activity-based models lack integrity across days of the week.Most of the available models simullate activity- travel patterns during one typical day while it is intuitively clear that if for any reason one lose opportunity to conduct an activity during one day, it does not mean that that activity fully disappears from his agenda but most likely for him to shift it to another day of the week.
# Longer time horizon
Developing dynamic models of activity- travel demand should be placed on research agenda. Not only exploring the effect of long-term decision such as moving residential locations on daily travel patten (top-down approaches) is of importance but also bottom-up effect which means daily frustration might ultimately leads to changes residential place needs to be more examined.
# Integrated with the use of Information and Communication Technologies (ICT)
The increasing availability of ICT in daily life, imply the necessity to integrate this effect with activity-based models.
# Integration of travel demand with network assignment
Most current operational activity-based models models rely on average travel times produced by static traffic assignment methods to provide Level-of-Service (LOS) measures to subsequent iterations of the ABM. Greater detail and fidelity in network performance is available from dynamic traffic assignment procedures and their use of time-dependent-shortest-path algorithms to produce detailed operating network trajectories for each traveler. This permits the ABM logic to be enhanced to adjust departure times and activity durations on-the-fly during assignment, rather than waiting to feed static LOS skims back through a global iteration to equilibrate.
A project undertaken by Chicago Metropolitan Agency for Planning (CMAP) in 2014 seeks to dynamically integrate the CT-RAMP platform for ABM with the Dynasmart-P platform for Dynamic Traffic Assignment. This approach is based on making the DTA vehicle trajectories available to CT-RAMP "on-the-fly" replacing (to a certain extent) reliance on level-of-service tables produced from static traffic assignment. This approach requires embracing an assumption of imperfect information and bounded awareness of discrete choice alternatives.
# Integration between travel and activity
Current activity based models differentiate between activity and travel. However, nowadays by omnipresent smart phones this boundaries is becomming blurred. Developing a conceptual framework for a comprehensive model is a line of future research.
# Source
Activity-Based Models of Travel Demand:Promises, Progress and Prospects (opens new window)